• Nutrition Research and Practice
• /
• 제8권5호
• /
• pp.526-532
• /
• 2014

BACKGROUND/OBJECTIVES: Acanthopanax sessiliflorus is a native Korean plant and used as a traditional medicine or an ingredient in many Korean foods. The free radical theory of aging suggests that cellular oxidative stress caused by free radicals is the main cause of aging. Free radicals can be removed by cellular anti-oxidants. MATERIALS/METHODS: Here, we examined the anti-oxidant activity of Acanthopanax sessiliflorus extract both in vitro and in vivo. Survival of nematode C. elegans under stress conditions was also compared between control and Acanthopanax sessiliflorus extract-treated groups. Then, anti-aging effect of Acanthopanax sessiliflorus extract was monitored in C. elegans. RESULTS: Stem extract significantly reduced oxidative DNA damage in lymphocyte, which was not observed by leaves or root extract. Survival of C. elegans under oxidative-stress conditions was significantly enhanced by Acanthopanax sessiliflorus stem extract. In addition, Acanthopanax sessiliflorus stem increased resistance to other environmental stresses, including heat shock and ultraviolet irradiation. Treatment with Acanthopanax sessiliflorus stem extract significantly extended both mean and maximum lifespan in C. elegans. However, fertility was not affected by Acanthopanax sessiliflorus stem. CONCLUSION: Different parts of Acanthopanax sessiliflorus have different bioactivities and stem extract have strong anti-oxidant activity in both rat lymphocytes and C. elegans, and conferred a longevity phenotype without reduced reproduction in C. elegans, which provides conclusive evidence to support the free radical theory of aging.

• 한국환경보건학회지
• /
• 제30권3호
• /
• pp.230-238
• /
• 2004

The adverse health effects of a number of environment pollutions are related to the formation of free radicals. Induction of antioxidant defensive system in the response to an oxidative attack is an essential element of the cell to survive. CYP2E1 is easily induced by organic solvents and induces continuous formation of reactive oxygen species (ROS). ${\gamma}$-Glutamyltranspeptidase (${\gamma}$GT) plays an important role in glutathione metabolism and xenobiotic detoxification. To evaluate the characteristic of oxidative stress which induces GGT expression and to understand human antioxidant defensive response against oxidative stress induced by CYP2E1, we studied regulation of ${\gamma}$GT enzyme expression in response to various oxidative stresses in human HepG2 cells. The ${\gamma}$GT activity was not modified after exposure of acute oxidative stress inducing agents (ferric nitrilotriacetate, cumene hydroperoxide, ADP-Fe, O-tetradecanoylphorbol-13-acetate, tumor necrosis factor-alpha). To induce continuous exposure of cells to ROS, HepG2 cells were transfected by human CYP2E1 gene transiently. The CYP2E1 activity was verified with chlorzoxazone hydroxylation. Transfection of CYP2E1 showed continuous 60% increase in intracellular ROS and 240 % increase in microsomal ROS. CYP2E1 overexpressing cells showed increased ${\gamma}$GT activity (2.5-fold). The observed enhancement of ${\gamma}$GT activity correlated with a significant increase of ${\gamma}$GT mRNA (2.1-fold). Treatment with antioxidant strongly prevented the increase in ${\gamma}$GT activity. The CYP2E1 overexpression did not modify toxicity index and increased glutathione levels. These results show that continuous exposure of cells to ROS produced by CYP2E1 up-regulates ${\gamma}$GT; This may be one of the adaptive antioxidant responses of cells to oxidative insult. Present study also suggests that the induction of ${\gamma}$GT could be used as a marker of oxidative stress induced by exposure to organic solvents.

• 한국식물생명공학회:학술대회논문집
• /
• 한국식물생명공학회 2002년도 추계학술대회
• /
• pp.49-58
• /
• 2002

Oxidative stress derived from reactive oxygen species (ROS) is one of the major damaging factors in plants exposed to environmental stress. In order to develop the platform technology to solve the global food and environmental problems in the 21s1 century, we focus on the understanding of the antioxidative mechanism in plant cells, the development of oxidative stress-inducible antioxidant genes, and the development of transgenic plants with enhanced tolerance to stress. In this report, we describe our recent results on industrial transgenic plants by the gene manipulation of antioxidant enzymes. Transgenic tobacco plants expressing both superoxide dismutase (SOD) and ascorbate peroxidase (APX) in chloroplasts were developed and were evaluated their protection effects against stresses, suggesting that simultaneous overexpression of both SOD and APX in chloroplasts has synergistic effects to overcome the oxidative stress under unfavorable environments. Transgenic tobacco plants expressing a human dehydroascorbate reductase gene in chloroplasts were showed the protection against the oxidative stress in plants. Transgenic cucumber plants expressing high level of SOD in fruits were successfully generated to use the functional cosmetic purpose as a plant bioreactor. In addition, we developed a strong oxidative stress-inducible peroxidase promoter, SWPA2 from sweetpotato (Ipomoea batatas). We anticipate that SWPA2 promoter will be biotechnologically useful for the development of transgenic plants with enhanced tolerance to environmental stress and particularly transgenic cell lines engineered to produce key pharmaceutical proteins.

• Journal of Microbiology and Biotechnology
• /
• 제17권9호
• /
• pp.1452-1459
• /
• 2007

The Dps protein, which is overexpressed in harsh environments, is known to playa critical role in the protection of DNA against oxidative stresses. In this study, the roles of Fur in the expression of the dps gene in Salmonella and the protection mechanisms against oxidative stress in Salmonella cells preexposed to iron-stress were investigated. Two putative Fur boxes were predicted within the promoter region of the S. typhimurium dps gene. The profile of dps expression performed by the LacZ reporter assay revealed growth-phase dependency regardless of iron-status under the culture conditions. The fur mutant, $_X4659$, evidenced a reduced level of ${\beta}$-galactosidase as compared to the wild-type strain. The results observed after the measurement of the Dps protein in various Salmonella regulatory mutants were consistent with the results acquired in the reporter assay. This evidence suggested that Fur performs a function as a subsidiary regulator in the expression of dps. The survival ability of Salmonella strains after exposure to oxidative stress demonstrated that the Dps protein performs a pivotal function in the survival of stationary-phase S. typhimurium against oxidative stress. Salmonella cells grown in iron-restricted condition required Dps for full protection against oxidative stress. The CK24 (${\Delta}dps$) cells grown in iron-replete condition survived at a rate similar to that observed in the wild-type strain, thereby suggesting the induction of an unknown protection mechanism(s) other than Dps in this condition.

• Journal of Plant Biotechnology
• /
• 제32권3호
• /
• pp.151-159
• /
• 2005

Injury caused by reactive oxygen species (ROS), known as oxidative stress, is one of the major damaging factors in plants exposed to environmental stress. Chloroplasts are specially sensitive to damage by ROS because electrons that escape from the photosynthetic electron transfer system are able to react with relatively high concentration of $O_2$ in chloroplasts. To cope with oxidative stress, plants have evolved an efficient ROS-scavenging enzymes such as superoxide dismutase (SOD) and ascorbate peroxidase (APX), and low molecular weight antioxidants including ascorbate, glutathione and phenolic compounds. To maintain the productivity of plants under the stress condition, it is possible to fortify the antioxidative mechanisms in the chloroplasts by manipulating the antioxidation genes. A powerful gene expression system with an appropriate promoter is key requisite for excellent stress-tolerant plants. We developed a strong oxidative stress-inducible peroxidase (SWPA2) promoter from cultured cells of sweetpotato (Ipomoea batatas) as an industrial platform technology to develop transgenic plants with enhanced tolerance to environmental stress. Recently, in order to develop transgenic sweetpotato (tv. Yulmi) and potato (Solanum tuberosum L. cv. Atlantic and Superior) plants with enhanced tolerance to multiple stress, the genes of both CuZnSOD and APX were expressed in chloroplasts under the control of an SWPA2 promoter (referred to SSA plants). As expected, SSA sweetpotato and potato plants showed enhanced tolerance to methyl viologen-mediated oxidative stress. In addition, SSA plants showed enhanced tolerance to multiple stresses such as temperature stress, drought and sulphur dioxide. Our results strongly suggested that the rational manipulation of antioxidative mechanism in chloroplasts will be applicable to the development of all plant species with enhanced tolerance to multiple environmental stresses to contribute in solving the global food and environmental problems in the 21st century.

• 동의생리병리학회지
• /
• 제21권3호
• /
• pp.671-678
• /
• 2007

Diabetes is a disease in which the body does not produce or properly use insulin. Etiological studies of diabetes and its complications showed that oxidative stress might play a major role. Therefore, many efforts have been tried to regulate free oxygen radicals for treating diabetes and its complications. Gamigukihwandong-hwan has been known to be effective for the treatment of diabetes. The present study was carried out to investigate the effect of Gamigukihwandong-hwan on renal function, peroxynitrite (ONOO$^-$) scavenging activity and polyol pathway in streptozotocin-induced diabetic rats. The crushed Gamigukihwandong-hwan was extracted 3 times, each time with 3 volumes of methyl alcohol at 60$^{\circ}C$ for 24 h. The extract was filtered and evaporated under a reduced pressure using a rotary evaporator to yield 74.95 g. Gamigukihwandong-hwan extract was oral-administered 100 mg per 1 kg of body weight for 20 days to the diabetic rats induced by streptozotocin (60 mg/kg). The effects of Gamigukihwandong-hwan extract on the streptozotocin-induced diabetic rats were observed by measuring the serum level of glucose, insulin, lipid components, creatinine and BUN, and also the kidney levels of superoxide anion radical (${\cdot}O_2^-$), nitric oxide (NO) and ONOO$^-$, and also the enzyme activities involved in polyol pathway. The Effects of Gamigukihwandong-hwan on the streptozotocin-induced diabetic rats with regards to body weight, blood glucose and insulin levels, creatinine and BUN levels, total cholesterol and triglyceride levels, and HDL-cholesterol levels were all shown to be good enough to cure and prevent the diabetes and its complications. Gamigukihwandong-hwan inhibited the generation of ${\cdot}O_2^-$, NO and ONOO$^-$ in the kidney of streptozotocin-induced diabetic rats. Renal aldose reductase and sorbitol dehydrogenase activities were increased in the streptozotocin-induced diabetic rats, whereas the ones in the Gamigukihwandong-hwan administered group among the streptozotocin-induced diabetic rats were reversed toward the natural activities. Gamigukihwandong-hwan might inhibit the development of diabetic nephropathy by scavenging reactive oxygen and nitrogen species, thereby by reducing oxidative stresses and also by regulating the activities of polyol pathway enzymes, all of which could help to recover the function of kidney.

• 한국육종학회지
• /
• 제41권3호
• /
• pp.261-270
• /
• 2009

1. 본 연구에서는 완두유래의 세포질성 PsAPX1 유전자를 대상으로 산화스트레스 유도성 프로모터를 연결하여 엽록체에 targeting 되는 과발현 운반체를 제작하고 벼에 도입한 결과 형질전환체에서 도입유전자 수가 1~3 copy인 것으로 나타나, 적은 수의 유전자가 안정적으로 도입되었음을 확인하였다. 2. 염, 오존, 자외선, 한발과 같은 다양한 환경스트레스 조건에서 내성이 증진된 우수 계통을 선발하기 위하여 작성된 형질전환 벼 계통들을 대상으로 생물검정을 실시한 결과, 독립계통별로 스트레스원에 대한 반응에 차이가 있음을 확인하였으며, 오존이나 자외선과 같은 산화스트레스 조건에서 내성이 증진된 우수 계통들을 선발하였다. 3. 이러한 결과를 바탕으로, 다양한 환경스트레스에 내성이 증진된 우수한 형질전환 벼 계통들을 선발하기 위하여 최소한의 독립라인을 작성하여야 함을 확인하였으며, 선발된 계통들은 새로운 육종 소재로 활용될 수 있을 것으로 기대된다.

• BMB Reports
• /
• 제41권3호
• /
• pp.194-203
• /
• 2008

Nitrosative modifications regulate cellular signal transduction and pathogenesis of inflammatory responses and neuro-degenerative diseases. Protein tyrosine nitration is a biomarker of oxidative stress and also influences protein structure and function. Recent advances in mass spectrometry have made it possible to identify modified proteins and specific modified amino acid residues. For analysis of nitrated peptides with low yields or only a subset of peptides, affinity 'tags' can be bait for 'fishing out' target analytes from complex mixtures. These tagged peptides are then extracted to a solid phase, followed by mass analysis. In this review, we focus on protein tyrosine modifications caused by nitrosative stresses and proteomic methods for selective enrichment and identification of nitrosative protein modifications.

• 한국패류학회지
• /
• 제32권2호
• /
• pp.73-81
• /
• 2016

Heat shock proteins (HSPs), one of the most highly conserved groups of proteins characterized to date, play crucial roles in protecting cells against environmental stresses, such as heat shock, salinity and oxidative stress. The glutathione S-transferases (GST) have important role in detoxification of oxidative stress, environmental chemicals and environmental stress. GST mRNA expression have been used as biomarkers on environmental stress. The purpose of this study was to investigate the death rate and the gene expression of Hsp70 and GST during air exposure and starvation. Results showed that, the expression of Hsp70 mRNA was significantly changed in the experiment groups, such as air exposure and starvation. GST mRNA expression was significantly increased in the experimental group of starvation. These results suggest that Hsp70 and GST were played roles in biomarker gene on the air exposure and starvation.

• Clinical and Experimental Pediatrics
• /
• 제51권1호
• /
• pp.54-61
• /
• 2008

목 적 : 특발성 신증후군의 연구를 위하여 병태생리 및 임상소견과 유사한 실험적 puromycin aminonucleoside(PAN) 신증을 이용하는데 본 연구는 배양한 사구체 상피세포에 대한 PAN의 영향을 통하여 신증후군의 주 원인 병태생리인 단백뇨의 기전을 밝히고자 하였다. 방 법 : 사구체 상피세포를 배양한 후 다양한 농도의 PAN과 항산화제를 투여하여 전자현미경관찰, 반응성 산소종 투과율 변화, confocal microscopy 등을 통하여 족세포성분의 변화를 관찰하였다. 결 과 : 사구체 상피세포의 초고배율소견에서 PAN에 의해 세포간극이 벌어지고 표면의 미세돌기가 단축되는 변화를 볼 수 있었다. 이러한 세포간극의 변화는 세포막부분의 ZO-1에 대한 면역형광검사에서도 확인할 수 있었다. DCF-DA로 측정한 반응성 산소종은 PAN에 의하여 농도에 따라 투여 2시간에 이미 유의한 증가를 보이나, 이러한 변화는 항산화제인 EGCG, probucol, vitamin C에 의해 감소하였다. 또한, 세포단층모델에서 투과율은 PAN에 의하여 농도에 따라 증가하나 항산화제에 의해 증가가 억제되었다. 세포골격구조인 ${\alpha}-actinin$은 사구체 상피세포의 세포질과 바깥 세포막부분으로 actin과 같이 분포하나 고농도의 PAN에 의해 세포질 바깥쪽의 일부분에 집중하는 형상으로 변하였다. 그러나 이러한 변화는 항산화제인 vitamin C의 처치에 의해 예방될 수 있었다. 세극막성분인 ZO-1는 고농도의 PAN에 의해 안쪽으로 이동하고 집중하는 형상으로 변하였으나, vitamin C의 처치에 의해 예방되었다. 이와 함께 ${\alpha}-actinin$과 ZO-1은 PAN에 의해 단백양이 감소하였으나 이는 항산화제에 의해 예방할 수 있었다. 결 론 : PAN은 사구체 상피세포의 반응성 산소종 생성을 증가시키고, 구조성분의 변화를 통하여 형태학적인 변화를 초래하며 이는 투과율의 증가로 나타났다. 이러한 변화들은 항산화제에 의해 어느 정도 억제할 수 있었음으로, PAN은 생체 외 사구체 상피세포에 산화스트레스기전을 통하여 구조적 변화와 이에 따른 단백뇨를 유발시키는 것으로 사료된다.